1. Field of the Invention
The present invention relates to portable radio communication apparatuses which employ various communication systems, and in particular, the present invention relates to foldable portable radio communication apparatuses.
2. Description of Related Art
Recently, portable communication apparatuses which employ communication systems which enable high-speed transmission of data, such as PDC (Personal Digital Cellular), CDMA (Code Division Multiple Access), GSM (Global System for Mobile Communication), and PHS (Personal Handy-phone System), are widely used. In addition, communication systems of the technologies of the next generation, such as WCDMA (Wide-band CDMA) and CDMA2000 are under development.
Among these types of portable radio communication apparatuses, ones having foldable structures so as to improve portability are known. However, a display section of such a portable radio communication apparatus of foldable type can not be seen from the outside when it is folded.
Therefore, there are portable radio communication apparatuses having structures such that the display function is maintained even when they are folded, which are provided with secondary display sections which can be seen from the outside even when the portable radio communication apparatuses are folded, as described in Japanese Unexamined Patent Application, First Publication (Kokai), No. Hei 6-37697.
However, even in a portable radio communication apparatus of this structure, there has been a problem that the contents on the exposed secondary display section are difficult to read in the nighttime or where illumination is dim.
Accordingly, one may consider providing each display section with a light to illuminate it; however, there has been a problem that such illumination of each display section with a light is a heavy load on the battery, and the battery runs out in a short time.
In addition, because of the provision of the secondary display section, there has been a problem that the above-described conventional portable radio communication apparatus consists of a large number of parts, which cause increase in the size of the case and damage the portability of the apparatus.
In particular, in order to allow each display section to display an image independently, each display section requires a driver which makes the display section display the image, and therefore the number of parts further increases, and the increase in the size was unavoidable.
In addition, with regard to the above conventional portable radio communication apparatus, if the second display section is disposed on the backside of the first display section, for example, a third person can view the second display when the user opens the portable radio communication apparatus in order to see the first display section.
In such a case, if the second display section is left on, there has been a possibility that the displayed contents can be seen, and there has been a problem that privacy may not be protected.